Razor blade sharpener



April 936. A. J. DREMEL 2,39,150

RAZOR- BLADE SHARPENER Filed Dec. 50, 1932 2 Sheets-Sheet l @KM s ATTORNEY Patented Apr. 2 8, 1936 UNITED STATES PATENT OFFICE 7 Claims.

This invention relates to an electrically driven razor blade sharpener.

Objects of this invention are to provide an electrically driven razor blade sharpener which is 5 equipped with sharpening rollers for simultaneously sharpening both edges of a double edged blade, the rollers operating on both sides of each edge, which has a simple and reliable form of drive from the electric motor to the sharpening rollers, and which is so made that the razor blade is carried back and forth, during the sharpening operation, by a blade carrier.

Further objects are to provide a power driven razor blade sharpener in which a novel form of blade carrier is provided which allows the blade to freely work or adjust itself to a slight extent as the blade is supported longitudinally adjacent its center, in which the sharpening rollers above and below the blade, are not directly opposed, but are spaced apart longitudinally to prevent gripping or forcibly engaging the delicate edge of the blade between the sharpening rollers, but instead, to allow the blade to slightly flex to yieldingly press itself against each roller, the blade being drawn back and forth by the blade carrier and avoiding all grooving or unequal sharpening.

Further objects are to provide a novel form of blade holder which is so made that it may be drawn outwardly through the front of the casing to receive the blade, which may be slid back and forth into and out of the casing to move the blade back and forth between the sharpening rollers.

Further objects are to provide a construction such as outlined above which allows the switch for the driving motor to close when the slide is drawn outwardly, which does not open the switch even when the slide is pushed back while carrying a blade, but which opens the switch when the blade is removed from the slide and the slide 40 pushed all the way back, the construction, therefore, dispensing with the use of an outside or extra switch, but instead insuring the starting of the motor, when a blade is to be sharpened, and the stopping of the motor when the operation of sharpening has been completed, the blade removed, and the slide pushed back into its housed position.

Further objects are to provide an electrically driven razor blade sharpener in which the motor is located above the sharpening rollers so that metal dust, parts from the blades and other matter from the sharpening rollers will fall away from the motor, in which the brush holders for the motor are carried or supported by the insulating end plates of the motor field coil, and inwhich a very compact, simple and easily and cheaply produced motor is provided and carried solely by a rear plate which latter also forms the main supporting means for the major portion of the entire mechanism.

Further objects are to provide a construction in which the frame for the mechanism is mounted within the casing in a simple manner without the use of screws or bolts, in which rubber or other yielding blocks hold the mechanism in place and provide a sound absorbing, cushioning means, and in which a back cover closes the casing and holds the blocks in place.

Further objects are to provide an electrically driven razor blade sharpener which is of very simple construction throughout, which is quiet in operation, which protects the user from the possibility of electrical shocks although the device may be left permanently connected to the electrical supply mains, and which is completely housed and may be hung from a vertical wall or may be placed upon a horizontal support.

An embodiment of the invention is shown in the accompanying drawings, in which:-

Figure 1 is a vertical sectional view through the casing of the device with parts of the mechanism shown broken away, such view corresponding to a section on the line ll of Figure 2.

Figure 2 is a rear view of the device with the back plate removed.

Figure 3 is a view of the front plate with the shafts for the sharpening rollers cut off and shown in section, such view showing in dotted lines the supporting lugs formed on the inner front face of the casing, such view corresponding to a fragmentary section on the line 33 indicated in Figures 1 and 4.

Figure 4 is a side view with parts broken away, showing the razor blade carrier, a portion of the shafts, the grinding rollers, and the slide for the razor blade carrier.

Figure 5 is a rear view of the back plate or main supporting plate for the mechanism.

Figure 6 is a side view of the structure shown in Figure 5.

Figure 7 is a top view of the switch plate and switch.

Figure 8 is a rear face view of the switch plate and switch.

Figure 9 is a fragmentary sectional view showing one of the rubber positioning and locking blocks in place.

Referring to the drawings, it will be seen that the device comprises a casing I which may be made of metal or of an insulating material, as

desired. This casing is closed by a back plate 2 held in place in any suitable manner, preferably, however, by spaced screws 3, as indicated. Preferably, as shown in Figure 2, three screw holes 4 are provided, one at the top and one at each corner of the device for correspondingly positioned screws The casing is provided with spaced guides or lugs 5 adjacent its rear portion, as shown most clearly in Figures 1 and 2. It is also provided with bosses 5 on its inner front side, see Figure 1, which are equipped with positioning lugs I, as shown in dotted lines in Figure 3.

The major portion of the mechanism is carried by a rear plate 8 which has outwardly pressed portions 9 to which the switch plate ID of insulating material, and hereinafter described, is secured by means of screws, as shown in Figure 2. The back plate 8 is provided with forwardly pressed portions providing bearings II for the ends of the sharpening roller shafts, the upper shafts being indicated by the reference character I2 and the lower shafts by the reference character I3, see Figures 1, 2, 3 and 4.

The rear plate 8 is provided with 2. turned over or horizontal portion I4, see Figure 6, which is cup-shaped to receive the self-centering bearing I5 of the vertical motor shaft I6, see Figures 2 and 6. Further this back plate is provided with forwardly turned lips or ears I! which are apertured and to which the field structure or yoke I8 of the motor is securely bolted.

As shown in Figures 1 and 2, a U-shaped upper bracket I9 is provided with outwardly projecting feet 20 which are apertured and upwardly pressed, as indicated at 2| in Figures 1 and 2. These upwardly pressed apertures 2| are threaded to receive the threaded ends of the clamping bolts 22 which clamp the motor frame or field structure to the back plate 8, and also clamp the U-shaped bracket I9, see Figures 1 and 2, in place. This U-shaped bracket is provided with apertures 23 through which the brushes 24 of the motor project without contacting with the metal bracket I9. This metal bracket also carries the upper self-aligning bearing 25 of the motor, the armature and commutator of the motor being indicated by the reference characters 26 and 21.

The field coil, indicated at 28 in dotted lines in Figure 1, is provided with insulating end plates 29 to which are rigidly secured the brush holders 30. These brush holders are each provided with brush receiving, cup-shaped portions 3I within which springs 32 are loosely housed, such springs urging the brushes inwardly, as is apparent from Figure 2.

The motor shaft I6 carries a driving worm 33 which meshes with the spaced gears 34 of the upper shafts I2, as is apparent from Figures 1 and 2. The gears 34 of the upper shafts mesh with the lower gears 35 carried by the lower shafts I3. This construction insures the correct motion of all of the rollers and provides a very simple, positive drive from the motor directly to the roller shafts. The gearing and direction of rotation of the motor is such that the lower portion of each upper sharpening roller hereinafter described travels outwardly, and the upper portion of each lower sharpening roller also travels outwardly so as to sharpen both edges of the blade simultaneously from both sides.

The shafts I2 are each provided with a pair of 's'pacedsharpening rollers 38 between which is located the corresponding sharpening roller 31 for the lower shafts I3.

If desired, a second sharpening roller corresponding to the roller 37 and spaced rearwardly therefrom may be employed without departing from the spirit of this invention. However, it has been found that the pairs of three rollers arranged as shown in Figure 1 is suflicient to give adequate sharpening for the razor blades.

The front end of each of the shafts I2 and I3 is carried in suitable bearing apertures formed in a front plate 38, see Figures 1 and 3. This front plate 38 is provided with notches 39, which, as shown in Figure 3, receive the positioning lugs I projecting inwardly from the front portion of the casing, as hereinbefore described.

The front plate 38 is cut away in its central portion and is provided with an integral rearwardly extending horizontal spacing strip 40, see Figure 4, which constitutes a guide for the razor carrier hereinafter described. This strip 40 also forms a supporting spacer which ties the front plate 38 to the rear plate, as shown most clearly in Figure 4. The strip 40 is fastened to the rear plate 8 by means of the screw 4| which screws into the member and clamps the spacer 4D betweenthe rear plate and the member 43. It will be seen that a screw 4I passes through the switch plate I0, through the rear plate 8, and through a downwardly turned lug 42 of the spacer and guide strip 40. A stop in the form of an upwardly projecting finger 43 is provided for a purpose hereinafter to appear, and is equipped with a downwardly turned portion 44, which is apertured and adapted for the reception of the threaded end of the screw II.

The blade carrier comprises a slide 45 which is freely passable, together with a blade, through an aperture 46, see Figure 1, formed in the front of the casing I. This carrier is provided with a manipulating knob or handle 41, see Figure 4, and rides upon the upper face of the guide strip 40. This guide strip, it will be noted from Figure 3, is provided with outwardly projecting portions which extend beyond the upturned end parts thereof. lnwardly turned flanges 48, see Figures 3 and 4, are formed on the carrier 45 and fit below the edges of the strip 40, as shown most clearly in Figure 3.

The carrier is provided with a downwardly projecting lug 49, see Figure 4, which is adapted to strike the front plate and prevent complete outward withdrawing of the carrier 45.

The carrier 45 is provided with an upwardly extending projecting portion 5|], see Figure 4, which enters the slot in the razor blade, such blade being indicated by the reference character 5I in Figure 4.

The carrier is also provided with an insulating disk or knoblike member 52 which is adapted to pass freely through the opening 53 of the switch plate I0, see Figures 2 and 8. When the slide or carrier 45 is pushed all the way back and when no razor blade is carried thereby, the member 52 will strike the spring arm 54 of the switch and move the upper end of the arm away from the stationary contact 55, see Figure 8, thus opening the motor circuit. However, when a blade, as shown in Figure l, is positioned on the carrier, the carrier is limited in its inward sliding motion by the striking of the blade 5| against the stop 43, and consequently the insulating member 52 cannot open the switch.

As previously stated, each upper shaft I2 carlies a pair of sharpening rollers-36 and each lower shaft carries a sharpening roller '31. In this connection it is to be noted from Figures 3 and 4 that the blade edge is not gripped tightly between immediately opposite rollers, but that the shapening rollers are spaced apart longitudinally of the blade. It is found that this construction does not tend to break the delicate edge of the blade, as the blade is allowed to flex and suitably adjust itself to the several rollers.

The upper shafts l2 are held in their correct position in suitable bearings formed directly in the front plate 38, see Figure 3. However, the lower shafts 53 are received in vertical slots l4 formed in the front plate 8 and are spring urged upwardly by means of the outwardly projecting arms of a spring 58. The central portion of the spring is arched upwardly and is hooked over an inwardly turned lip 55, see Figures 3 and 4, struck and bent inwardly from the front plate 38. The outwardly projecting arms of the spring fit within grooves iifi formed in the shafts l3, as shown in Figure 4, and thus yieldingly urge the sharpening rollers towards each other.

In assembling the apparatus, the unitary mechanism is slipped into place from the rear of the device and the front plate 38, see Figure 3, engages the lugs 'i on the inner front side of the casing. The rear plate is notched out on opposite sides, as indicated at 6!, and a pair of rubber cushioning and positioning blocks 62, as shown particularly in Figures 2 and 9, are slipped into place between the guiding lugs 5 and the notched portion 6| of the back plate 8.

The rubber blocks 52 are provided with tongues 53 which fit within the notches El and are provided with shouldered portions 64 which abut the rear plate. The outer ends of the rubber blocks 62 abut the back plate 2 of the casing. Thus the entire mechanism is held in place without the use of additional screws or bolts. In addition, these rubber blocks 62 form a cushioning sound absorbing means which makes the apparatus very quiet, as a majority of the vibration of the mechanism occurs adjacent the gearing and motor, and at this portion of the device these cushioning blocks are provided.

In addition to this, it will be seen that the device is very simple to assemble, is composed of a small number of relatively easily produced parts, and is compact.

When the device is not in use the razor blade carrier 45 is pushed all the way back and the member 52 holds the switch in open position. When it is desired to use the device, the carrier is pulled forwardly and the motor immediately starts. A razor blade is positioned, as hereinbefore described, and the carrier is slid back and forth so as to pass the edges of the blade back and forth between the rollers. It is impossible to inadvertently stop the operation of the apparatus, as the backward travel of the carrier is limited, as the blade 5| will strike against the stop is, see Figure 4, and prevent the member 52 from opening the switch, as has been described. However, when the carrier is finally drawn completely forward and the blade removed and thereafter pushed back into housed position, the apparatus is automatically stopped as the switch is then opened. No additional switch is required and the device may be left permanently connected with the supply mains.

It is obvious that the apparatus may be rested upon a horizontal support and left permanently in place. On the other hand, if desired, it may be suspended from a vertical wall by means of the eyelet 65, see Figures 1 and 2 formed integrally with the casing.

It will be seen that the suspension means is located above the motor and the associated sharpening mechanism and consequently the suspension means is above the center of gravity of the structure. This suspension means may be hung upon a hook or other projection carried by a vertical wall and the device may be left permanently in place. Also it is to be noted that the casing will bear against the wall adjacent the bottom and that a laterally extended contact is had with the wall to prevent rocking of the casing. The device has been found to be remarkably steady when hung upon a hook carried by a vertical wall and may be most easily operated while in this position so that the operator does not have to pick it up and handle it as in the heretofore known types of razor Sharpeners. In addition to this, it may be hung from other supports than that specifically discussed.

From actual use it has been found that the apparatus is very reliable in operation and that the sharpening of the razor blades is thorough and rapid.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

I claim:

1. A razor blade sharpener comprising sharpening rollers, an electric motor for driving said sharpening rollers, a switch controlling said motor, a slidable razor blade carrier for holding a razor blade and for moving such blade past said sharpening rollers, and means for opening said switch when said carrier is pushed inwardly a predetermined distance.

,2. A razor blade sharpener comprising sharpening rollers, an electric motor for driving said sharpening rollers, a switch controlling said motor, a slidable razor blade carrier for holding a razor blade and for moving such blade past said sharpening rollers, means for opening said switch when said slide is pushed inwardly a predetermined distance, and a stop engageable by a blade carried by said carrier to limit the inward motion of said carrier when said carrier carries a blade, whereby said motor will not be stopped while said carrier carries a blade.

3. A razor blade sharpener comprising a casing, an electric motor mounted in the upper portion of said casing and having a downwardly projecting shaft, a worm carried by said shaft, four substantially horizontal rolled shafts, sharpening elements independently carried by each of said last mentioned shafts, gears carried by two of said horizontal shafts and meshing with said worm, a gear carried by each of the other two horizontal shafts and respectively meshing with said first mentioned gears, and a razor blade carrier for positioning a double edged razor blade with both its edges between said sharpening rollers.

4. A razor blade sharpener for sharpening a double edged blade, said sharpener comprising four spaced sharpening rollers arranged in staggered pairs for simultaneously sharpening all faces of both edges of the blade from both sides thereof, a blade carrier slidable longitudinally inwardly and outwardly beyond the ends of all of said rollers during sharpening, four shafts for said sharpening rollers, a single electric motor for simultaneously driving said four shafts, said motor having .a drive shaft, andgearing operatively connecting said drive shaftand said'four shafts.

5. A razor blade sharpener comprising a casing, sharpening rollers mounted within said casing, an electric motor for driving said sharpening rollers, and a razor blade carrier projecting through said casing and slidable back and forth to present the blade to said rollers, and an electric switch controlling said motor, said switch being opened by said carrier when said carrier is moved inwardly a predetermined distance.

6. A razor blade sharpener comprisinga back plate and a front plate mechanically joined as an assembled unit, horizontal shafts carried by said plates and provided with sharpening rollers, a blade carrier for presenting a blade to said sharpening rollers, an electric motor having a field structure carried by said back 'plate and hav- 'ing an armature provided with a drive shaft,

bearings for said drive shaft supported from said back plate, and means operatively coupling said horizontal shafts and said drive shaft.

7. A razor blade sharpener comprising a back plate and a front plate mechanically joined as an assembled unit, horizontal shafts carried by said plates and provided with sharpening rollers,

ing an armature provided with a drive shaft,

bearings for said drive shaft supported from said back plate, and means operatively coupling said horizontal shafts and said drive shaft, said motor having a field winding provided with insulating end plates and having brush holders carried by said insulating end plates.

ALBERT J. DREMEL. 

